From e3e31369a74343daa8edd0b77b1a1714f713701c Mon Sep 17 00:00:00 2001
From: mtkennerly <mtkennerly@gmail.com>
Date: Fri, 15 Sep 2023 02:02:35 +0800
Subject: [PATCH] #67: Fix cases where log.excludeDecoration is configured

---
 CHANGELOG.md                      |  5 +++++
 dunamai/__init__.py               | 12 +++++++-----
 tests/integration/test_dunamai.py | 27 ++++++++++++++++++++++++++-
 3 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a4d1f7c..ebc5346 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## Unreleased
+
+* For Git 2.16+, `--decorate-refs=refs/tags/` is now specified for `git log`
+  in case you've configured `log.excludeDecoration=refs/tags/`.
+
 ## v1.18.0 (2023-07-10)
 
 * Added a `vcs` attribute to `Version` to indicate which VCS was detected.
diff --git a/dunamai/__init__.py b/dunamai/__init__.py
index fc55bd8..7ad2ae1 100644
--- a/dunamai/__init__.py
+++ b/dunamai/__init__.py
@@ -474,18 +474,20 @@ def normalize_tag_ref(ref: str) -> str:
             return "refs/tags/{}".format(ref)
 
     @staticmethod
-    def from_git_tag_topo_order(tag_branch: str) -> Mapping[str, int]:
-        code, logmsg = _run_cmd(
+    def from_git_tag_topo_order(tag_branch: str, git_version: List[int]) -> Mapping[str, int]:
+        cmd = (
             "git log --simplify-by-decoration --topo-order --decorate=full"
             ' {} "--format=%H%d"'.format(tag_branch)
         )
-        tag_lookup = {}
+        if git_version >= [2, 16]:
+            cmd += " --decorate-refs=refs/tags/"
+        code, logmsg = _run_cmd(cmd)
 
-        # Simulate "--decorate-refs=refs/tags/*" for older Git versions:
         filtered_lines = [
             x for x in logmsg.strip().splitlines(keepends=False) if " (" not in x or "tag: " in x
         ]
 
+        tag_lookup = {}
         for tag_offset, line in enumerate(filtered_lines):
             # lines have the pattern
             # <gitsha1>  (tag: refs/tags/v1.2.0b1, tag: refs/tags/v1.2.0)
@@ -1158,7 +1160,7 @@ def from_git(
                 )
 
             detailed_tags = []  # type: List[_GitRefInfo]
-            tag_topo_lookup = _GitRefInfo.from_git_tag_topo_order(tag_branch)
+            tag_topo_lookup = _GitRefInfo.from_git_tag_topo_order(tag_branch, git_version)
 
             for line in msg.strip().splitlines():
                 parts = line.split("@{")
diff --git a/tests/integration/test_dunamai.py b/tests/integration/test_dunamai.py
index 44aaa34..ea18c6e 100644
--- a/tests/integration/test_dunamai.py
+++ b/tests/integration/test_dunamai.py
@@ -4,7 +4,7 @@
 import time
 from contextlib import contextmanager
 from pathlib import Path
-from typing import Callable, Iterator, Optional
+from typing import Callable, Iterator, List, Optional
 
 import pytest
 
@@ -15,6 +15,12 @@ def avoid_identical_ref_timestamps() -> None:
     time.sleep(1.2)
 
 
+def lacks_git_version(version: List[int]) -> bool:
+    if shutil.which("git") is None:
+        return True
+    return _get_git_version() < version
+
+
 REPO = Path(__file__).parent.parent.parent
 
 
@@ -451,6 +457,25 @@ def test__version__from_git__shallow(tmp_path) -> None:
             Version.from_git(strict=True)
 
 
+@pytest.mark.skipif(lacks_git_version([2, 27]), reason="Requires Git 2.27+")
+def test__version__from_git__exclude_decoration(tmp_path) -> None:
+    vcs = tmp_path / "dunamai-git-exclude-decoration"
+    vcs.mkdir()
+    run = make_run_callback(vcs)
+    from_vcs = make_from_callback(Version.from_git)
+    b = "master"
+
+    with chdir(vcs):
+        run("git init")
+        (vcs / "foo.txt").write_text("hi")
+        run("git add .")
+        run("git commit --no-gpg-sign -m Initial")
+        run("git tag v0.1.0 -m Release")
+        run("git config log.excludeDecoration refs/tags/")
+
+        assert from_vcs() == Version("0.1.0", dirty=False, branch=b)
+
+
 @pytest.mark.skipif(shutil.which("git") is None, reason="Requires Git")
 def test__version__not_a_repository(tmp_path) -> None:
     vcs = tmp_path / "dunamai-not-a-repo"